Two days ago i downloaded Release 1.6.0 to test the Zend_Soap_Client. The code

$Response = $Client->get_echo('test');

crashed (under XP / Apache 2.2 / PHP5.2.6)

The code

$Client = new SoapClient('../server/soap_test.wsdl', $Options);

$Response = $Client->__call('get_echo', array('test'));

did work.

I found that
Zend_Soap_Client_Common::__doRequest(...)
was called (on $this->_soapClient member of Zend_Soap_Client), this one called
Zend_Soap_Client::_doRequest(...)
which again called
Zend_Soap_Client_Common::__doRequest(...)
(I think, the base call SoapClient::__doRequest(...) was indented?)
and so on.

I am not so familar with the architecture to locate the reason for this.

In this way extensions of Zend_Soap_Client can do some work ( in overwriting Zend_Soap_Client:: _doRequest(...) ), before the actual soap call is done.
Eliminating Zend_Soap_Client_Common:: __doRequest(...) will undo this, because then SoapClient:: __doRequest(...) will be called immediately.